<!DOCTYPE HTML>
<html>
	<head>
		<meta charset = "utf-8">
		<style type="text/css">
			.container{
				height: 1080px;
				width: 1920px;
				display: none;
				overflow: hidden;
			}

			.pic>img{
			    height: 1080px;
				width: 1920px;
				
			}
		</style>
	</head>

	
	<body>
		<div id="ad" class="container">
			<img class="pic" id="adpic" src="img/28.jpg">
		</div>
	 <script type="text/javascript">
		window.onload = function(){
	 		var ad = document.getElementById('ad');
	 		var adpic = document.getElementById('adpic');
	 		var h = 0;
	 		var maxh = adpic.height;
			setTimeout(picDown,3000);
	 		function picDown() {
		        if(h<maxh){
		        	h += 10;
		            ad.style.height= h + 'px';
	 	        	ad.style.display = 'block';
		        	setTimeout(picDown,1);
               }else{
                	ad.style.height= h + 'px';
                   ad.style.display = 'block';
                    setTimeout(picUp,3000);
                }

	 		}
			
	 		function picUp(){
			if(h>0){
					h -= 10;
		            ad.style.height= h + 'px';
 	            setTimeout(picUp,1);
		        }
	 		}
	 	}

	 </script>

	</body>

</html>